Water filter



Se t. 19, 1944, E. H. THOMPSON WATER FILTER 2 Sheets-Sheet 1 Filed Feb. 14, 1941 60 INVENTOR fihrzest 17 2720122 Sept. 19, 19. I H THOMPSON 2,358,748

WATER FILTER Filed Feb. 14, 1941 2 Sheets-Sheet 2 Patented Sept. 19, 1944 WATER FILTER Ernest H. Thompson, Winnetka, Il1.,'assignor to Automatic Canteen Company of .America, Chicago, 111., a corporation of Delaware Application February 14, 1941, Serial No. 378,854

2 Claims.

This invention relates to a water filter. More particularly it relates to a water filter for use in conjunction with a drink vending machine wherein water is to be filtered as rapidly as required for the preparation of beverages.

Carbonated beverages prepared and dispensed by most ,types of vending machines are not as uniform in taste noras freefrom alien matter asarebottled beverages for the reason that bottlers generally use filtered water in the preparation of beverages while most operators of drink vending machines, use whatever. tap water is available at the location of the vending machine. In some localities tap wateris so free from impurities that the difierence between a beverage prepared from tap water and a beverage prepared from filtered water can not be detected,

but localities in which such tap water is available are few. The impurity or the turbidity of the water availableat most vending machine locations is sufficiently great to impair thetaste of a beverage prepared from it. Moreover, many communities, introduce various amounts 'of chlorine to the water and, chlorinated water retains the chlorine taste in most'beverag'es prepared from it.

Some operators ct drink, vending machines have sought to overcome thisquality differential between bottled beverages and vending machine beverages by supplyingfiltered water to the vending machines. This procedure is successful but has the disadvantage of introducing a water hauling problem of serious proportions. For every gallon of syrup or beverage concentrate that must becarried bya vending machine service man, there must be carried four to six times as much filtered water, which in turn affects the size and typeof truck to be used by the service men.

To eliminate this hauling problem, applicant proposes to filter water in thevending machine and to use in conjunction with'the filter some substance such. as'activated carbon for removing chlorine. Filtering water in a vending machine encounters serious obstacles due to vending machine design and tothe method of servicing vending machines. In those beverage vending machines which are portable, that is, those which do not require a water pipe connection, all water for beverages is obtained from a water "reservoir within the vending machine and this water reservoir is filled periodically by a service man. The capacity of the water tank is five or six times that of the capacity'of the syrup tank or tanks and the vending machine is permitted to function until it hasexhausted or nearly exhausted the ingredients for preparing beverages, at which time the machine is automatically locked. If a filter is positionedv in the lower part of the water tank, one of'two difi'iculties are encountered depending upon whether the water reaches the mixing assembly by gravity or by means of a pump. If the machine design, 'employs a gravity system, .water will not pass through the filter as rapidly as required when the vending machine is operating during a heavy load period, with the result that in orderto keep the machine continuously in' commission, a second reservoir for filtered water approximating in size the reservoirof unfiltered water must be placed in the vending machine. Space is ata premium in vending machines and this second reservoir,

consequently, is not wanted. On the other hand,

if the machine design employs a pump for delivering the water to the mixing assembly, the filter must be located in the water line in such a way that it can be removed from the water line only by opening water tight couplings. Because it is not practical to send qualified technical men to vending machine locations for the purpose of opening water lines andcleaning or exchanging filter elements, and because the average service man is not qualified to' do this work, filtering Water in vending machines has not reached a commercial stage of development.

The first object of this invention is to utilize the suction of a vending machine pump for filtering'the water as rapidly as required for the preparation of beverages while nevertheless so positioning the filter element between the water reservoir and the beverage mixing assembly that water tight couplings need not be opened in order to remove the filter element. One of the features ofthis invention is the positioning of a filter element on the low side of the pump inside the water reservoir in such a manner that the pump can obtain water from the water reservoir only by drawing it through the filter element regardless of the depth of the water in the tank while the filter element itself, nevertheless, may be quickly removed from the tank. By this arrangement, the ordinary service man (one who fills water and syrup tanksand cup magazines) may remove the filter element for cleaning purposes without touching any of the'pipe fittings.

Another object of this inventionis to provide means for substantially emptying the water reservoir so that the vending machine locking mechanism may be set to lock the machine only when the water tank ,has become. practically empty. 'While .it would appear comparatively simple to position a filter near the bottom of a water reservoir so as to permit a pump to suck water into a space therebelow, obtaining the' necessary seal between'the filter element and the inside tank wall is possible only by sacri-' ficing ready removability of the filter. In order to provide a filter having a large surface area and yet having the ability to substantially empty the water reservoir,'applicant has positioned a filter element of considerable height on an outlet in the bottom of the reservoir and over this i filter element has positioned an air-tight hood jair-tighthood and until the water level reaches the openings in the hood near the bottom of the hood, at which time, the. suction in the hood be destroyed. andthe sys'temwill cease to function." Inasmuch as thisbccurs when the water'reservoir is substantially empty the machine will'have become locked by other means in the. vending machine.

j 'A further object of this invention is to assemble the filter element and the air-tight hood intoa single assemblywhich may be referred .to as a filter cartridge andprovide simple means for removably mountin this filter cartridge in the outlet of the water reservoir. Applicant provides interior threads on the'res'ervoir outlet fitting'and a threaded member on the cartridge, .whereby a service man may remove the top of the water reservoir and screw the filter cartridge into the threaded means. An elongated handle on the upper portion of the cartridge makes it possible to do this without reaching any great .distance into the water reservoir.

I A further object of this invention is to provide a filtermember which is readily removable from the filter cartridge so that a service man on location need only clean the inside of means such as threads 26 are provided for couthecartridge if the filter element itself is in such condition that he cannot clean it.- By this arrangement a service man may carry replacement filter elements and it will never be necessary to place the vending machine'out of commission while the filter element is being returned to a plant for-cleaning." A further object of this invention is to provide a removable bottom for the filter cartridge in conjunction with the positioning of inlets to the filter cartridge at a point slightly above the .bottom. By this arrangement a basin is provided in the bottom of the filter cartridge for catching sludge. 'This removable bottom being shallow is readily cleaned.

Another object of this invention is to position the openings into-the filter cartridge at a and notbe disturbed by water flowing into the 57.

filterpartridge. In many communities water 1containsavery largefamount of suspended matter whichl will collect onthe bottom of whateveryessel is holding the water when the water is'at rest; It is highly'de'sirable that this action be not impaired during the cycling of a Vending machine because it materially reduces the work of the filter and thereby increases the time between filter element exchanges or filter cleanmgs.

Applicants invention includes other features. One of which is the provision of a large tapering end on the means for assembling the filter cartridge with the water reservoir outlet whereby a service man without looking down into the reservoir, which may be difiicult due to the .vending machine design, will be able to assemble quickly the filter cartridge once the tapered filter cartridge taken on the line' 3'3 of Figurel; V M Figure 4 is a view in section of a modified form of applicants invention} and V Figure 5 is asectional view taken on the line 5 '5 of Figure 4'. v w Continuing to refer to the drawings, and particularly to Figure 1, the numeral l0 identifies a side wall of a water reservoir and I2 the bottom of the water reservoir. Referring to Figure. 3, in a hole I4 is positioned a pipe fitting is which is maintained in" water tight relationship with the bottom I2 bymeans of seals l8 and and a nut' 22. Any other type of water tight fitting would serve as well. The inside wall of the fitting 16 is threaded at 24 and other pling a water line 21, schematically shownin Figure 1, leading toa purnp 28. The filter carfridge comprises a hood, being a metal jacket,

' "which is air tight throughout its height excepting for holes near its lower edge which is closed byv a removable sludge pan 32.

fit'between a flange 34 around the circumfer- A fairly tight ence of the sludge pan'32 and the outer bottom portion of the wall of the filter cartridge 30 is provided. in order to hold the two in assembled relationship while nevertheless permitting a service man to removeeasily the sludge pan 32 ,for purposes of cleaning orfor Femoving the filter element. A hole 35 is centrally positioned ,in the sludge pan 32. The .top end wall 38 of the filter cartridge 30 has at its center a hole 49 of the same size as the hole 36 and a nut'42 establishes a water tight connection between a handle 44 and the filter cartridge 30 when a tubular supporting member 54 is drawnup tight therein. The handle 44 is interiorly drilled and threaded at 46. It may be of any desired length, depending upon the depth of the water reservoir, and has finger gripping means such as 48 and 50. see Figure l, on the ,upper end. A plurality of holes 52 through the flange 34 are in registry with holes 3! in the filter cartridge 30 and to- ,gether provide passageways for water from the reservoir into the filter Qartridgeiltl.

r The filterelement, generally identified by the numeral 10, consists. ofthe tubular supporting member 54 havingeach end threaded asat 55 and 58 with a taperedguide tip60 on .one. end. The tubular supporting member 54 is perfo- :rated'by a plurality of holes (i2 andthistprforated portion ofthe' tube is-surrounded by a water permeable filter element comprising a filter casing held inposition'by ring mem bers Stand 68. Disposed between the filtercasing 54 and the tubular supporting-membertil is any suitable substance such as activated carban for moving from water certain undesirable substances such as chlorine.

' It will be'observed that the holes 52 are post-l tioned slightly above the bottom of thereser-Q voir. This is for the purpose of reducing water The filterelement is a unit itselffiwhen the filter cartridge '30 has been removed from thereservoir, the filter element may be re moved from the cartridge by removing the sludge pan 32 and unscrewing the tubular supporting member 54 from the nut 42 and the" handle 44. The two ends of the filter element are identical so that it is immaterial which end is mounted inside the filter cartridge. :a

Importance is not attached to the height of the filter element or the filter cartridge. The dimensions of the filter element will conform to the dimensions of the filter cartridge and the dimensions of the filter cartridge may be varied to suit the particular water reservoir in use in any given Vending machine. The filter car tridge would perform its function if it were short and broad or again, if it were taller. The

limit of its effective height is, of course, the.

limit to which atmospheric pressure will force water vertically through the holes 52.

In operation. assuming that the water reservoir is full at the time when the filter cartridge is screwed into the fitting Hi, the first cycle of the vending machine will cause the pump to create a partial vacuum on its low side, that is, inside the tubular supporting member 54. Because air will pass through the filter element 10 with greater ease than will water, water will be drawn through the openings 52 upwardly around theentire filter element 10 so as to fill the filter cartridge completely. In actual practice one cycle of a vending machine which draws about five ounces of water for each drink will fill the filter cartridge with water. Subsequent cycling of the vending machine will direct water through the filter element and through the holes 62 in the tubular supporting element 54 downwardly through the opening 12 into the pipe leading to the pump 28. The filter will continue to function as the water level drops downwardly, referring to Figure 1, until the reservoir has been emptied so that the water levelestands at 1.4. During all of this time the air-tight hood 30 has remained full of water and the suction of the pump has been fairly effective in drawing water through the filter element 10 at all points into the tubular supporting member 54. When the water reaches the level 14, air enters the airtight hood 3 0. When this occurs, the filter will no longer supply filtered water to the pump as required and it is essential that the vending machine be in locked condition when the water drops to this level. The manner of locking the vending machine 7 is generally made dependent upon the number of drinks drawn. maintaining a safe margin, or by some water level device.

' It will he appreciatedv .thatxin one' aspect zapplicants invention :resides inpositioning awater filter having a large filter area intermediate a water reservoir and a suction'pump without holding the-height of the fi ter to a point 'below' the lowest level of the water inthe reservoir desired to be reached before the reservoir mustbe refilled.- Applicant draws water up into a filter cartridge and then provides means for passing the water through a comparatively-large filter =element where-by the capacity of the filter 'remains high and substantiallyuniform regardless of varyingdepths of the wateriin the reservoir.

The. advantages of applicantsiinvention are many; 'In" the first-place it is no longer necessary to haul water from a filtration plant :to the location ofthe vending machine. Additionally, it is possible to-utilize=the suction of the pump to filter water as rapidly as the' vending'machine requires it and under such circumstances that the removal 'of-the' filter does not require the rapidly as required, a vending machine equipped with applicants filter, which machine has been rendered inoperative because of lack of water,

may b placed in condition for resumption of operation by simply filling the tank and cycling the machine once.

From the servicing standpoint the filter cartridge and the means for assembling it with the water reservoir have great advantages. It is not necessary to have a skilled mechanical man make filter exchanges. A regular service man may remove the cartridge from th tank, clean the sludge (latching element 32, the filter element 10 and the inside of the air-tight hood 30. He may reassemble them, no particular skill being required, and mount the air-tight hood 30 in the water reservoir.

In Figures 4 and 5, there is shown a modified form of applicants invention. In .this form of the invention, th supporting tube 54 is permanently mounted on the hoodlelement 30' and in place of a plurality of ports such as 62, shown in Figure 3, the supporting tubular element 54' is provided with four or eight comparatively large holes such as M and 16. The filter element is a distinct unit comprising a hollow cylindrical core 18, rolled from perforated sheet metal. The ends of this hollow cylindrical core may be turned down to form two collars 80 and 82 or these collars may be provided as distinct elements, as the designer may wish. The filter-material disposed within th fabric 84, for example, cotton filter cloth, may be held in assembled relationship by any suitable means such as wire wrappings or the like. In order to provid a tight seal between the inside of the filter element. and the hood 30' and the reservoir outlet fittings, sponge rubber seals 86 and 88 are proivded.

It will be noted that the inside diameter of the cylindrical core 18 substantially exceeds the outside diameter of the supporting tubular element 54', with the result that any drop in pressure established by the pump within the tubular element 54' will be equally established in that annular space 9!), see Figur 5, between the cyment 54 is drilled with only a few large holes, such as 14 and 16, and is spaced from the cylindrical core 18 which is rolled inexpensively from perforated sheet material. -Having thus described my invention, what I -claimv as newand desire to secure by Letter Patent of the United States is: V

1. A water filter assemblage comprising a water reservoir, an outlet disposed in the lower portion of said reservoir, a water conduit opening into said reservoir outlet and extending upwardly into the water reservoir, a plurality of ports in the walls of said conduit, a filter element over said ports, an air-tight hood supported on the upper end of said water conduit and extending down- -wardly to a point below the bottom of the filter lement, an opening in the lower part of the side of said hood communicating with said reservoir,

and a sludge catch basin disposed around said water conduit to form a bottom for said air-tight :hood' without interfering with the admission of water into said hood, whereby much of the sludge accumulations may lbO readily removed from the jfilter cartridge by removing the sludge catch basin and cleaning it.

2. A water filter assemblage comprising a water reservoir, an outlet disposed in the lower portion of said reservoir, a supporting tubular member .in communication with said outlet and extending upwardlyinto said reservoir, a hoodmember sealed to the upper part of said supporting tubular member'and extending downwardly toward the bottom of said reservoir, ports in the walls of, said tubular member above the bottom of said hooded member, an inlet from said reservoir near the bottom ofsaid hood member, and a removable filter element havinga perforated cylindrical core disposed around said tubular supporting member.

-- Y ERNEST THOMPSON. 

